Firefox has a lot of the features in that Opera list (or plug-ins that do them if the core doesn't). Opera is definitely faster than FF, but I cannot get used to the layout (and it's no-script equivalent is next to non-functioning in terms of ease of use). I'm willing to trade speed for a better user experience, which boils down to what you're used to.

And FF has private browsing like incognito - Ctrl + Shift + p